Not Applicable.
Not Applicable.
The present invention relates to a burner tube for use with a cooking chamber. More specifically, the present invention relates to an elongated curvilinear burner tube having a union region that forms a continuous, multi-directional passageway for the flow of fuel.
The popularity of gas barbecue grills and gas outdoor cooking devices has increased tremendously over the last twenty-five years. In contrast to charcoal barbecue grills, gas barbecue grills employ a burner assembly that requires a combustible fluid, for example, propane or natural gas, as a fuel source. Barbecue grills with gas burner elements have proven extremely popular with consumers because they provide controlled, uniform heat distribution. In addition, gas burner assemblies are relatively simple to operate and generally require less maintenance and clean-up time.
Conventional gas burner assemblies typically include a plurality of linear burner tubes, control valves, and a manifold. Each burner tube has a first end and a second end, and a plurality of fuel outlet ports spaced between the first and second ends. The first end of the burner tube is connected to a control valve which meters the flow of fuel. The first end and the control valve are connected to the manifold which is linked to a fuel source, for example, a propane tank. Therefore, multiple burner tubes extend from the manifold. The second end of the burner tube is closed or crimped such that fuel cannot flow past the second end. Accordingly, fuel from the fuel source flows in only one linear path, from the first end to the second end of the burner tube.
Conventional burner assemblies require specific construction and assembly that are susceptible to higher cost and related limitations. First, due to the fact multiple burner tubes are required to form a burner assembly, the material, labor, and assembly costs are significant. These costs are compounded by the fact that each burner tube may require a separate inlet assembly, including a venturi element and a control valve. Further, because the second end of burner tubes are closed or crimped, the first end of each burner tube must be connected to a manifold, thereby limiting the configuration of the burner assembly. Consequently, the versatility of conventional burner assemblies is reduced because such assemblies cannot be uniquely configured or utilized in a wide variety of cooking chambers.
An example of a burner assembly susceptible to the limitations identified above is U.S. Pat. No. 5,676,048 to Schroeter et al. As shown in FIGS. 2 and 11 therein, a burner assembly 17 is formed from the combination of a linear burner tube 18 and two xe2x80x9cL-shapedxe2x80x9d burner tubes 24. The linear burner tube 18 has a first end 19 and a closed or crimped second end 20. Referring to FIG. 12, the L-shaped burner tube 24 has a primary member 25, a secondary member 28, and a curved elbow segment 31. The first end 26 of the L-shaped burner tube 24 is open, while the second end 30 is closed. Consequently, in either burner tube 18, 24, fuel is constrained to flow in a single pathxe2x80x94from the first end to the closed second end.
Another example of a burner assembly with the concerns identified above is U.S. Pat. No. 5,890,482 to Farnsworth et al. As shown in FIG. 2, the burner assembly is formed from the combination of six (6) burner tubes 14. Each burner tube has a venturi element, an inlet valve assembly, a first series of outlet ports, and a second series of outlet ports. Referring to FIG. 3, the burner tube 14 has a first segment 44, a second segment 42, and a curved elbow segment 46. The first segment 44 is open while the second segment 42 has a closed end. Accordingly, in the burner tubes 14, fuel flows from the first end to the closed second end.
Yet another example of a burner assembly of the prior art construction is U.S. Pat. No. 6,102,029 to Schlosser et al., which is assigned to the Assignee of the present invention. As shown in FIGS. 3-5, the burner assembly 10 generally comprises a first burner tube 21, a second burner tube 22, a third burner 23, and a crossover tube 24. The second burner tube 22 is positioned between the first and second burner tubes 21, 23 to form a burner grid 20. Each burner tube 21, 22, 23 has a first end with a venturi assembly 32 connected to a control valve 30 of the manifold 16. The second end 25 of the first, second, and third burner tubes 21, 22, 23 is closed. A crossover tube 24 ports with an orifice 28 located upstream of the second end 25 in the first and second burner tubes 21, 22. The crossover tube 24 is in fluid communication with only the first burner tube 21 and the third burner tube 23. Accordingly, the crossover tube 24 serves as a pilot tube for either the first or third burner tube 21, 23. The closed, second end 25 of the second burner tube 22 has a flange 40 that is adapted to be received by a stock connection 42 attached to the crossover tube 24. Since the second burner tube 22 is not in fluid communication with the crossover tube 24, the second burner tube 22 only receives fuel from the manifold 16. Therefore, in the second burner tube 22, fuel can only flow from the first end to the second end.
Therefore, there is a need for a continuous burner assembly formed from a burner tube wherein fuel can flow in multiple paths or directions throughout the burner tube. Also, there is a definite need for a continuous burner assembly which is compact and capable of being employed in a wide variety of cooking chambers. In addition, there is considerable need for a continuous burner assembly with a single inlet valve assembly to minimize the overall size of the burner assembly while providing an enlarged burner flame area.
The present invention is provided to solve these and other deficiencies.
The present invention relates to a burner for use with a cooking chamber. More specifically, the present invention relates to a continuous burner constructed from an elongated burner tube having a proximal segment, a distal segment, and a terminal end in fluid connection with a union region of the proximal segment. Due to the fluid connection between the terminal end and the union region, the burner has a curvilinear configuration and defines a multi-directional passageway for the flow of fuel throughout the burner.
The proximal segment is adapted to be connected to a fuel source, i.e., a fuel tank. The distal segment is downstream of the proximal segment. The terminal end is connected to the burner tube at a union or interference region of the proximal segment. The connection between the terminal end and the union region forms a continuous burner tube with a multi-directional passageway. This means that fuel from the fuel source can flow throughout the burner tube, including the proximal segment, the distal segment, the union region, and the terminal end. Specifically, fuel can flow from the proximal segment through the union region and into and through the terminal end. The burner tube has a plurality of fuel outlet ports or apertures from which flames extend. An ignitor is used to ignite fuel that has exited the outlet ports along the burner tube to form a burner flame area.
The burner tube can have a variety of configurations, including a generally obround or rectangular configuration. Preferably, the distal segment has at least one curvilinear portion, which facilitates the connection of the terminal end with the union region. Due to the mating of the terminal end with the proximal segment, the burner tube defines an enclosed central region. The terminal end is connected to the union region whereby the continuous, integral burner tube is formed. The connection between the terminal end and the union region is facilitated by the curvilinear portion. The terminal end can have a necked portion with a tapered diameter, and a mating portion. The mating portion is either partially or entirely received by an aperture in the union region. Once received by the aperture, the terminal end is in fluid communication with the union region of the proximal segment. The fluid communication between the union region and the mating portion defines a passageway or control volume for fuel to flow throughout the burner tube.
In accord with the invention, the burner tube is in a first position P1 wherein the terminal end is connected to the union region. Due to the curvilinear configuration of the distal segment, the terminal end is biased towards the union region. This biasing causes the terminal end to be lockingly engaged to, or secured with the union region in the first position P1. In a second position P2, the terminal end is unconnected or disengaged from the union region and due to the biasing described above, a portion of the terminal end extends past the union region. Also, in the second position P2, the terminal end is vertically misaligned with a plane defined by the burner tube. The second position P2 generally represents an unassembled status of the burner tube. Once aligned with the aperture, the biasing of the burner tube will cause the terminal end to lockingly engage the union region.
In the first position P1, fuel flows from the fuel source in an initial flow path through the proximal segment and into the union region. Flow separation occurs generally within the union region. A first flow path F1 flows past the union region and downstream to the distal region. Because the terminal end is in fluid communication with the union region, a second flow path F2 flows past the union region and downstream into the terminal end. Therefore, fuel from the fuel source can flow in one of two distinct paths, downstream into the distal region or downstream into the terminal end.
In further accord with the invention, the terminal end has a mating portion that is in fluid communication with the aperture of the union region. The mating portion can be received by the aperture. Structure of the mating portion can extend past the aperture such that an edge or wall of the mating portion extends into the union region. This results in alteration of the fuel flow in the union region. As a result, a first portion of fuel flows through the union region and downstream into the distal region and a second portion of fuel flows through the union region and downstream into the terminal end. The geometry of the mating portion and the degree or amount that the mating portion extends past the aperture affects the flow of the fuel in the burner tube.
Other features and advantages of the invention will be apparent from the following specification taken in conjunction with the following drawings.